RFR: 8354455: [TestBug] Remove JUnit Vintage Engine with JUnit 4 [v2]

[Marius Hanl]

> These are the remaining bits and pieces in order to completely remove the JUnit Vintage Engine, and therefore JUnit 4 from JavaFX.
> After that, we should either document, that JUnit5 is used (just as information) or close [JDK-8296284](https://bugs.openjdk.org/browse/JDK-8296284) (Since you can not use JUnit4 anymore).
> 
> This also removes the `org.hamcrest` dependency, which is actually only used in one test where it can easily be replaced by a `Predicate` (instead of `Matcher`). I'm not convinced that we should keep that dependency for just one test.
> 
> Note: I could not get the `:swt` tests to compile/test, in order to run the tests. 
> I need some guidance here how to instruct `Gradle` to compile this module (and if I need anything else? like swt?).
> 
> Also, this probably needs an extra ticket in the JBS?

Marius Hanl has updated the pull request incrementally with one additional commit since the last revision:

  Fix SWT Tests

-------------

Changes:
  - all: https://git.openjdk.org/jfx/pull/1774/files
  - new: https://git.openjdk.org/jfx/pull/1774/files/60262b5e..dc7925f7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jfx&pr=1774&range=01
 - incr: https://webrevs.openjdk.org/?repo=jfx&pr=1774&range=00-01

  Stats: 205 lines in 4 files changed: 101 ins; 15 del; 89 mod
  Patch: https://git.openjdk.org/jfx/pull/1774.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1774/head:pull/1774

PR: https://git.openjdk.org/jfx/pull/1774